American Society of Home Inspectors (ASHI)
2767 Dewey Avenue
Rochester, NY 14616
Office: 585-349-3900
Fax: 585-349-3834
www.InspectNY.com

E-Mail GHI
Gunther Home Inspections...

Credit Cards
New York State #16000005972

Facebook

Home Page About GHI "HOME"
Feature Topics Feature Topics
Contact us

Contact Us (585) 349-3900

www.InspectNY.com

 

Water-Immersed NM Cable

Gunther Home Inspections

To Whom it may concern:

Safety tips for water-immersed Type NM-B nonmetallic-sheathed cable, i.e.,
Romex®


Type NM-B nonmetallic-sheathed cable (commonly called "Romex®" in the industry) is Listed by UL for use in normally dry locations in accordance with the National Electrical Code® (NEC®) under the product category "Nonmetallic-sheathed Cable (PWVX)." General Guide Information for this category can be found in UL's Online Certifications

Directory.

Decades ago, the outer jacket of this cable changed from an impregnated, braided
covering to polyvinyl chloride (PVC). In the mid-1980s, the internal conductor insulation went from a temperature rating of 60°C to a 90°C rating, and the required marking was changed from "Type NM" to "Type NM-B."

The older, braided jacketed version of this cable has less resistance to water ingress than the newer, PVC-jacketed version, and if subject to immersion, such as from flooding, the suitability for continued use is unknown. Any cable of this type that has been subjected to flooding should be replaced without question.

In general, cables with PVC insulation and jacket can withstand immersion in clean water for a short period of time without being damaged as long as the ends are not immersed. If the ends of the cable are immersed for any period of time, however, the internal paper wrapping around the bare equipment-grounding conductor will absorb and transfer the water into the cable assembly. The water may then start degrading the insulation or possibly corrode the conductors. If the cable comes into contact with contaminated water, the contaminants may also act on the insulation or conductors. Over time, failures can occur.

In a flooding situation, there is no way of knowing how long the cables were immersed in water, or what types of potentially corrosive substances may have been in the water that flooded the cables. As was widely reported after Hurricane Katrina, raw sewage and chemicals were known to be in the floodwaters afflicting the Gulf Coast region of the United States. Nonmetallic-sheathed cable has not been investigated by UL for this type of exposure. Therefore, it is not possible for UL to state that cable in a particular installation is acceptable for continued use after having been subjected to the flooding. The safest approach is to replace any nonmetallic-sheathed cable that was immersed in water for any period of time during the flooding.

The devastation of a flood is enormous. As the contaminated waters recede, there may be even more threats to your personal health and safety. By taking basic precautions, you can help prevent many injuries. IAEI and UL urge you to always put the safety of your family first.

For more information, contact your local electrical inspector or visit www.iaei.org

 


Should you have questions, problems or
suggestions regarding our web site please contact our WebMaster

[ ABOUT GHI HOME ][ HOME INSPECTION ][ INSPECTION FEES ][ SET AN APPOINTMENT] [RADON TESTING ][ PEST INSPECTIONS ][ CUSTOMER TESTIMONIALS ][ FEATURE TOPICS] [ BROKERS AND REAL ESTATE AGENTS ][SCHEDULE APPOINTMENT ON-LINE][CONTACT US ]

Gunther Home Inspections, Inc.
Voice 585-349-3900 - Fax 585-349-3834
2767 Dewey Avenue - Rochester, NY 14616 - www.InspectNY.com
NYS# 16000005972
 © 1998-2012 Gunther Home Inspections, Incorporated